Fact SheetThe Visible Human Project®

Background

The National Library of Medicine (NLM) has seen an increasing use of electronic images for clinical medicine and biomedical research. The Visible Human Project was established in 1989 to build a digital image library of volumetric data representing complete, normal adult male and female anatomy.

Visible Human Male

The Visible Human Male data set, released in November 1994, consists of MRI, CT, and anatomical images. Axial MRI images of the head and neck, and longitudinal sections of the rest of the body were obtained at 4mm intervals. The MRI images are 256 by 256 pixel resolution with each pixel made up of 12 bits of gray tone. The CT data consist of axial CT scans of the entire body taken at 1mm intervals at a pixel resolution of 512 by 512 with each pixel made up of 12 bits of gray tone. The approximately 7.5 megabyte axial anatomical images are 2048 pixels by 1216 pixels, with each pixel being .33mm in size, and defined by 24 bits of color. The anatomical cross-sections are at 1mm intervals to coincide with the CT images. There are 1,871 cross-sections for both CT and anatomical images. The complete male data set is approximately 15 gigabytes.

Higher resolution axial anatomical images of the male data set were made available in August 2000. Seventy-millimeter still photographs taken during the cryosectioning procedure were digitized at a pixel resolution of 4096 pixels by 2700 pixels. These images, each approximately 32 megabytes in size, are available for all 1,871 male color cryosections.

Visible Human Female

The Visible Human Female data set, released in November, 1995, has the same characteristics as the The Visible Human Male. However, the axial anatomical images were obtained at 0.33 mm intervals. Spacing in the "Z" dimension was reduced to 0.33mm in order to match the 0.33mm pixel sizing in the "X-Y" plane. As a result, developers interested in three-dimensional reconstructions are able to work with cubic voxels. There are 5,189 anatomical images in the Visible Human Female data set. The data set size is approximately 40 gigabytes.

Applications

The Visible Human data sets are designed to serve as a reference for the study of human anatomy, to serve as a set of common public domain data for testing medical imaging algorithms, and to serve as a test bed and model for the construction of network accessible image libraries. The Visible Human data sets have been applied to a wide range of educational, diagnostic, treatment planning, virtual reality, artistic, mathematical, and industrial uses by nearly 2,000 licensees in 48 countries. Several applications have been developed at the National Library of Medicine or under the direction of the National Library of Medicine. These applications include:

AnatLine is a prototype system consisting of an anatomical image database and an online browser. This prototype was developed by the Lister Hill Center for Biomedical Communications at the National Library of Medicine to provide a client/server Internet interface to access gross anatomy images of the human body. This version of AnatLine consists of image records of thoracic cross sectional planes, thoracic voxel structures, and rendered bitmap images. These images were scanned from the 70mm film cross section data set and digitized in a 4096x2700 pixel frame size. This diditized collection of cross section images was aligned and segmented into 434 throacic structures. AnatLine's Anatomical Browser provides online viewing of low resolution surface rendered images of the human throacic region.http://vhnet.nlm.nih.gov/Anatline/

Insight Toolkit (ITK) - ITK is an open source public software system developed by six principal organizations, three commercial( Kitware, GE Corporate R & D, and Insightful, and three academic (UNC Chapel Hill, University of Utah, and University of Pennsylvania)with additional input from Harvard Brigham & Women's Hospital, University of Pittsburgh, and Columbia University. ITK supports image analysis research in segmentation, classification, and rigid deformable registration techniques to process high dimensional medical data. ITK employs leading-edge segmentation and registration algorithms in two, three, and more dimensions. ITK is implemented in C++. ITK is cross-platform using the CMake build environment to manage the compilation process. In addition, an automated wrapping process generates interfaces between C++ and interpreted programming languages such as Tcl, Java, and Python (using CableSwigThis enables developers to create software using a variety of programming languages. ITK's C++ implementation style is referred to as generic programming (i.e., using templated code). Such C++ templating means that the code is highly efficient,and that many software problems are discoverd at compile-time, rather than at run-time during program execution. http://www.itk.org